Field of the Invention
The present invention relates to a composition for nanoimprint and a nanoimprint pattern forming method.
Priority is claimed on Japanese Patent Application No. 2015-083209, filed on Apr. 15, 2015, the contents of which are incorporated herein by reference.
Description of Related Art
A lithography technology is a core technology of a semiconductor device process, and further miniaturization of wiring has been promoted with high integration of a semiconductor integrated circuit (IC) in recent years. As the miniaturization method, a method of shortening the wavelength of a light source by means of using a light source having a shorter wavelength such as a KrF excimer laser, an ArF excimer laser, an F2 laser, extreme ultraviolet light (EUV), electron beams (EB), or X-rays or a method of making the diameter of a numerical aperture (NA) of a lens of an exposure device large (making the NA large) is typically exemplified.
In these circumstances, nanoimprint lithography in which a mold on which a predetermined pattern is formed is pressed against a substrate formed with a resin layer on the surface thereof and the pattern of the mold is transferred to the resin layer has been suggested.
In the nanoimprint lithography, optical nanoimprint lithography using a composition for nanoimprint that contains a photocurable resin cured by light (ultraviolet rays or electron beams) has been suggested. In this process, a mold is pressed against a resin layer including a photocurable resin, the resin layer is irradiated with light so as to cure the resin, and the mold is peeled off from the resin layer, thereby obtaining a transfer pattern (structure).
As characteristics generally required for the composition for nanoimprint used for the nanoimprint lithography, coating properties required when a substrate is coated with the composition using spin coating or the like or curing properties required when heating or exposing is performed are exemplified. When the coating properties are degraded, the film thickness of the composition for nanoimprint, which is applied to the substrate, becomes uneven and this leads to deterioration of pattern transferability at the time when a mold is pressed. In addition, the curing properties are important characteristics because the pattern formed by pressing the mold is maintained at a desired size.
For example, Patent Literature 1 discloses a composition for nanoimprint in which polymers are blended at a predetermined blending ratio and coating properties and curing properties are improved.